Carbon sequestration driver: Spiders, why did it have to be spiders?

A new study shows that the predator-prey relationship can affect the flow of carbon through an ecosystem. This previously unmeasured influence on the environment may offer a new way of looking at biodiversity management and carbon storage for climate change.

The study, conducted by researchers at the Yale School of Forestry & Environmental Studies, comes out this week in the Proceedings of the National Academy of Sciences. It looks at the relationship between grasshoppers and spiders—herbivores and predators in the study’s food chain—and how it affects the movement of carbon through a grassland ecosystem. Carbon, the basic building block of all organic tissue, moves through the food chain at varying speeds depending on whether it’s being consumed or being stored in the bodies of plants. However, this pathway is seldom looked at in terms of specific animal responses like fear from predation.

“We’re discovering that predators are having important effects on shaping the make-up of ecosystems,” says Dr. Oswald Schmitz, professor of ecology and one of the co-authors of the study. “But we’ve not really spent a lot of time measuring how that translates into other functions like nutrient cycling and recycling.”

The researchers manipulated the food chains of grassland ecosystem to see how the levels of carbon would change over time. Dr. Schmitz and his team created several controlled ecosystems: some that contained only native grasses and herbs, others that had plants and an herbivore grasshopper, and some others that had plants and herbivores along with a carnivore spider species—all three tiers of the food chain. In addition, a form of traceable carbon dioxide was injected into sample cages covered with Plexiglas, which allowed the team to track the carbon levels by periodically taking leaf, root, and dead animal samples.

The study found that the presence of spiders drove up the rate of carbon uptake by the plants by about 1.4 times more than when just grasshoppers were present and by 1.2 more times than when no animals were present. It was also revealed that the pattern of carbon storage in the plants changed when both herbivores and carnivores were present. The grasshoppers apparently were afraid of being eaten by the spiders and consumed less plant matter when the predators were around. The grasshoppers also shifted towards eating more herbs instead of grass under fearful scenarios.

At the same time, the grasses stored more carbon in their roots in a response to being disturbed at low levels when both herbivores and carnivores were present. In cases where only herbivores were present, the plants stored less carbon overall, likely due to the more intense eating habits of the herbivores that put pressure on plants to reduce their storage and breathe out carbon more. These stress impacts, then, caused both the plants and the herbivores to change their behaviors and change the composition of their local environment.

This has significance for biodiversity conservation and ecosystem management. Although the study was carried out on a small scale, it could inform practices done in much larger areas. Places such as the Alaskan wilderness, for example, are home to animals that have the same predator-and-prey dynamics that drive the carbon cycle, and so protecting lands and storing carbon could be linked at the same time. Appreciating the role of predators is also important currently, given that top predators are declining at rates faster than that of many other species in global trends of biodiversity loss.

“It’s going to force some thinking about the vital roles of animals in regulating carbon,” concludes Dr. Schmitz, pointing to the fact that the UN’s body of scientific experts who study climate change don’t consider these multiplier effects in their models. “People are arguing for a paradigm change.”

Spiders are some of the most fascinating creatures. I love them. I stay away from the poisonous ones that can hurt (Daddly longlegs are one of the most poisonous, but their mouth is not wide enough to bite you)., but try to preserve the ones around my house (my wife makes me get rid of the ones INSIDE the house).

The amount of annoying bugs they eat is awesome! That is why I do encourage them everywhere in my yards. beats chemicals!

So, I should tell she who must be obeyed that I won’t kill that spider because I’m saving the planet? Right.
“Carbon” instead of the appropriate form? Do we need to study diamond sequestration effects on global warming?

“It’s going to force some thinking about the vital roles of animals in regulating carbon,” concludes Dr. Schmitz, pointing to the fact that the UN’s body of scientific experts who study climate change don’t consider these multiplier effects in their models. “People are arguing for a paradigm change.”

Gee, one more thing the GCMs don’t consider relevant. What a surprise!

If it wasn’t for spiders and scorpions we would be knee deep in insects.

As a matter if fact I have a pet spider in my studio where the computer sits. I have scattered crumbs which led to a few roaches showing up. When Schmidt (her name, she’s a wolf spider) showed up they disappeared. I even saw her catch one. Fortunately my beloved Libby doesn’t know about her.

From the article:This previously unmeasured influence on the environment may offer a new way of looking at biodiversity management and carbon storage for climate change.

Carbon storage??? We barely have enough to feed the carbon-based life forms we have right now on earth. We can’t wait around for geologic processes to replenish the supply. The precautionary principle states that we must do what we can to liberate enough carbon to support current and future life. Liberating carbon by burning coal, oil, and gas just isn’t cutting it. We need to try something else. I’ll start breathing easier when we get up around 600-700ppm.

Well, at least they did a real experiment instead of just using computer models. But what a tragedy that they then polluted their paper with climate crap. OTOH, no-one would have noticed their paper otherwise. Such is the corruption of science.

“The researchers manipulated the food chains of grassland ecosystem to see how the levels of carbon would change over time. Dr. Schmitz and his team created several controlled ecosystems: some that contained only native grasses and herbs, others that had plants and an herbivore grasshopper, and some others that had plants and herbivores along with a carnivore spider species—The researchers manipulated the food chains of grassland ecosystem to see how the levels of carbon would change over time. Dr. Schmitz and his team created several controlled ecosystems: some that contained only native grasses and herbs, others that had plants and an herbivore grasshopper, and some others that had plants and herbivores along with a carnivore spider species—all three tiers of the food chain..”

“all three tiers of the food chain.” Really? A grassland ecosystem may not be the most complex environment on the planet, but any natural iteration of one would be at least 3-5 orders of magnitude more complex than this grossly over simplified experimental apparatus. The “three tiered food chain” would extend all the way down to at least the bacterial level and up to, as Mr. Rasey suggested above, the top predator, humanity. Even if we stipulate to the data they collected with this work, extrapolating from it to any conclusions about what is happening in the real world wouldn’t seem to be entirely, or even slightly, justified.
That being said, they should at least be credited for having the wit to realize that world is much more complex than the available models can simulate. Now if we can just get them to realize that just because we can measure the radiative characteristics of a CO2 molecule in a tightly constrained laboratory experiment, it doesn’t necessarily mean we can predict with any degree of certainty what CO2 will do when circulating with all the other hundreds of influences at work in the climate and environment of the planet. Each responding in their own way to the laws of nature and science in ways that interact, overlap, contradict or enhance each other with such complexity as to be virtually unfathomable, at least at this point. It likely never will be fathomable if we continue invest (squander) all our time, energy, and financial resources on a element of the problem that more and more appears to be significant only as a pretext for the expansion of social and political control.

Bob says (June 17, 2013 at 1:53 pm): “So, I should tell she who must be obeyed that I won’t kill that spider because I’m saving the planet? Right.”

When my daughter grew old enough to empathize with living things, I had the excuse I needed to switch from a KILL ON SIGHT!!! policy to capture-and-release, incidentally earning a few Daddy Points in the process. Now that the Princess is out on her own, I still deal humanely with wildlife-in-the-wrong-place, but the Red Queen sometimes beats me to it.

Time to remove about 80% of the grants from the environmental and climate sciences and get back to a situation where scientists did that science because they wanted to. And not because there is a very comfortable life style to be had by getting big tax payer funded grants using the latest fancy and deliberately misleading language and then churn out large volumes of total BS that is paraded as science and all set up to get more grants from a public that is increasingly weary of paying for all the truckloads of seriously bad science which is all most of these misnamed “scientists” can ever rise to,

This study is about carbon uptake not carbon storage.
Maximum uptake (they measured it with tracers) is under the light to moderate grazing option with the grazers numbers controlled by predators. Carbon is being recycled so more goes through..
While the no grazing option may start quicker it quickly reaches the water, nutrient or light limit and stops taking more carbon up. However the no grazing version gives the maximum carbon storage option.
CSIRO Ecological Sustainability people found the “same” a decade ago measuring plant biodiversity which is maximum under light to moderate grazing.
While it may be useful additional proof that complex systems are more productive, the reference to carbon storage and “climate change” is just a red herring to get more attention!

(from phone call this evening to yours truly — oh, yes, we women stick together. #[;)] — as best as I could recall it)

Libby: Hello, Janice? What’s this I see about an ENORMOUS spider in Stanley’s studio?
[you see, Stan, she DOES go on WUWT and reads what you write…. heh, heh, heh….]
Janice: Oh. Ah, weeelll…. I don’t think it will hurt you… . If you see it, just pound on the floor next to it and it will run away and hide. It just wants to —-
L: I DON’T CARE!! Whatareyousomekindofanaturefreakorsomething?! Spiders like that could run and hide ANYWHERE!!!!!!
J: You’re right. That’s why I smash them if I find them inside the house… . But, Libby, Stan really likes this spider. I think it’s like, well a pet or something. Just don’t go into the studio.
L: Oh, I’ll do better than that… .

BTW: Not sure you read it, but THANK YOU, SO MUCH for your kind, MUCH-needed, words of encouragement the other day. (I left a thank you on the thread about no more snow in CA mountains).

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And, here’s “an engineer’s take” (Ronald D. Voisin in June 14, 2013 thread, in Summary)
“***
6. The current spike in atmospheric CO2 would most likely be larger than now observed if human beings had never evolved. The additional CO2 contribution from insects and microbes (and mammalia for that matter) would most likely have produced a greater current spike in atmospheric CO2.”
[See https://wattsupwiththat.com/2013/06/14/an-engineers-take-on-climate-change-2/#more-88092%5D

Yes Janice, I read it and can’t wait to show it to Libby who does know about Schmidt in spite of what I said above. A little commenters license? Schmidt has also disappeared since the bugs disappeared.

“We’re discovering that predators are having important effects on shaping the make-up of ecosystems,” says Dr. Oswald Schmitz, professor of ecology and one of the co-authors of the study.
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He’s just figuring that out? A Professor of Ecology, in 2013? Oh, my.

And yes, another “study” (like the silly aquarium ones that pretend to simulate the ocean) which ignores 99% of the interactions that occur in the real, vastly complex ecosystem they are looking at.

PS – Praying Mantis are my favourite garden predators. But when I see all the insects caught in spiderwebs in summer, I am thankful for them, even if they are not easy to like.

This is interesting but not unexpected. The problem is that these scientists will want to manipulate an area to confirm their data then enlarge that area to include huge swathes of a country to try to increase carbon sequestration which is not needed. Any interference in the environment is to be deplored since serious unintended consequences are never known therefore not taken into account.
Let nature take its course, Do not interfere.

Doing field work in Tanzania, I startled a small group of giraffes. A calf quickly suckled its mother, several of the adults defecated and then they all took off. I guess some carbon got used up.

Anyway, how significant is 1.2 and 1.4 more carbon and the difference between them? Did they repeat the experiment many times? Were the plants all the same size, stage, seed development onset..?. Was there variability in the size, metabolism, activity of the grasshopper, spider? Did they have a dozen terrariums? Steve McIntyre? Wm Briggs? what do you say about such a piece of work. I think 1.2/1.4 verification must require 5 to 10 repeats.

“It’s going to force some thinking about the vital roles of animals in regulating carbon,” concludes Dr. Schmitz, pointing to the fact that the UN’s body of scientific experts who study climate change don’t consider these multiplier effects in their MODELS. “People are arguing for a paradigm change.”

I hate grasshoppers. They’re impossible to eradicate and they destroy gardens. A few years ago, a huge spider made a web in our hedges. Every day,when I came home from work, I would feed him a nice juicy grasshopper. The spider would wrap him up in webbing, and leisurely feed on him. After a week or so, the spider would no longer eat the grasshoppers, but go hide in the corner of the web. About a week after that, the spider disappeared. Don’t know if I overfed him and he “popped” or what.

At least the author got to do what he really wanted, which was to study spiders. All he had to do was mutter a few incantations about the climate and it got all paid for. I saw this exact same thing on a show a couple of years ago, it might have been Nova. Scientists were studying the geometric distribution of plants and their mass and relating that to fractals. At the very end, they measured the carbon content of a couple of leaves and said a few words about “climate change.” It was obvious their real intent was the former, not the latter.

Unless I missed something, the researchers did not measure the “carbon” stored by the living herbivores, carnivores or the waste products of both. Neither are there any measurements showing atmospheric CO2 changes for the differing scenarios. Whenever a study uses the term “carbon” to refer to carbon dioxide, my BS meter pegs out. “Scientists” who use this term are automatically showing their bias, and any conclusions they may come to are most probably incorrect.